Statistical and spectral analysis of the wind regime in the area of Catalonia

Summary This work presents a statistical study of the wind power potential of three stations in the Catalonia area (Spain) over the 1973–1982 period. These stations correspond to three airports (Barcelona, Palma de Mallorca and Girona), which obviously do not present a high wind power potential and are not the suitable locations for wind power utilization, but which have been chosen for the long record of data stored (10 years). The aim of this work is to provide a model of wind potential in terms of the speed and wind direction, which may be applied to other sites. The wind speed has been modelled by a Weibull distribution function and the wind direction by a normal two-dimensional function. A spectral analysis of both variables has also been carried out. The present study provides an evaluation of the local wind power in the geographic area of Catalonia.With 10 Figures     

A contribution to the measurement of frequency dependence of electrical conductivity of rocks

Summary Some errors of method occurring in A. C. measurements of the electrical conductivity of rocks are discussed. It is demonstrated that the difference between A.C. and D.C. conductivities, at given frequency, depends mostly on the magnitude of the D.C. conductivity and magnitude of the dielectric constant.     

Improved indirect phase reflection height measurement at panská ves — method,equipment, evaluation

Summary Indirect phase reflection height measurements have been performed at the Panská Ves Observatory, Czechoslovakia, for 30 years to monitor solar flare effects (SFA). Only after introducing the new receiver in May 1985, could the indirect phase height analysis (IPHA) method be applied to measurements along the Allouis — Panská Ves 162 kHJ measuring path. The IPHA method allows the electron density and pressure variability in the lower ionosphere to be studied, particularly near the 80 km altitude. This paper describes the theoretical background of the IPHA method, the measuring equipment used at Panská Ves, the method of evaluating records and checking of data, and the program package developed by us both for graphic and numerical processing, as well as our efforts to develop a homogeneous East European IPHA network. The IPHA method has been introduced succesfully at the Panská Ves Observatory.     

Barotropic model of the atmosphere and short-term variations in the lod

Summary The classical barotropic model is used to indicate the possible connection between the intensification of atmospheric westerlies and the acceleration of the Earth's rotation.     

A summary of sulfur dioxide emission rate measuremnts from Guatemalan volcanoes

Measurements of the sulfur dioxide (SO₂) emission rate from three Guatemalan volcanoes provide data which are consistent with theoretical and laboratory studies of eruptive and shallow magma chamber processes. In particular, unerupted magma makes a major contribution to the measured SO₂ emission rates at Santiaguito, a continuously erupting dacitic volcanic dome. Varying shallow magma convection rates can explain the variations in SO₂ emission rates at Santiaguito. At Fuego, a basaltic volcano currently in repose, SO₂ emission rate measurements are consistent with a high level magma body that is crystallizing and releasing volatiles. At Pacaya, a continuously erupting basaltic volcano, recent SO₂ emission rate measurements support laboratory simulation studies of strombolian eruptions; these studies indicate that the majority of gas escapes during eruptions and little gas escapes between eruptions.Average SO₂ emission rates over the last 20 years for Santiaguito, Fuego and Pacaya are 80, 160 and 260 Mg/d, respectively. On a global scale, these three volcanoes account for 1% of the annual global volcanic output of SO₂. Santiaguito and Pacaya, together, emit 6% of the total annual SO₂ emitted by continuously erupting volcanoes.Even though SO₂ measurements at these volcanoes have been made infrequently and by different investigators, the collective data help to establish a useful baseline by which to judge future changes. A more complete record of SO₂ emission rates from these volcanoes could lead to a better understanding of their eruption mechanisms and reduce the impact of their future eruptions on Guatemalan society.     

Parameters of the Earth's tri-axial level ellipsoid

Summary Four parameters defining the Earth's tri-axial ellipsoid (E) have been derived on the basis of the condition that the gravity potential on E be constant and equal to the actual geopotential value (W₀) on the geoid. The geocentric gravitational constant, the angular velocity of the Earth's rotation, the actual 2nd degree geopotential Stokes parameters and W₀ are taken to be the primary geodetic constants defining E and its (normal) gravity field.     

Determination of period of oscillation and sensitivity of simple horizontal pendulums for tidal measurements

Studia Geophysica et Geodaetica - Авторы уже раньше...     

Statistical determination of the law of dispersion of marking material in the shattered zone

Studia Geophysica et Geodaetica -